共查询到20条相似文献,搜索用时 546 毫秒
1.
针对静态微悬臂梁表面特异性结合产生表面应力信号的响应机制问题,介绍了微悬臂梁生化传感器的工作原理,阐述了应力响应机制的简化模型,从纵向界面上和横向分子间2个方面对特异性吸附引起的悬臂梁表面应力的变化进行了剖析,讨论了界面能变化、位阻作用、静电力、氢键作用等与表面应力大小及方向之间的关系,总结了应力型微悬臂梁生化传感器的响应机理的研究。 相似文献
2.
3.
4.
谐振微悬臂梁是一种可以将质量变化转换为频率信号的微质量型传感器,因其分辨率高、灵敏度高、成本低、易于集成和小型化等优点而备受关注。谐振微悬臂梁现已被广泛应用于流量控制、生物医学痕量检测、气态和液态分子分析等领域。近年来,随着微机电系统(Micro-Electro-Mechanical System,MEMS)技术的快速发展,针对谐振式微悬臂梁传感器的研究与应用越来越多,对近年来谐振式微悬臂梁传感器在环境检测、生物医学等领域的具体应用进行了综述,并对未来的发展方向做出了展望。 相似文献
5.
6.
扭转谐振模态微悬臂梁低能耗、高品质因数的特性,使它比传统的弯曲模态悬臂梁拥有更高的灵敏度和分辨率.将微传感器加工技术和生物检测技术相结合,利用扭转谐振模态微悬臂梁传感器对生物素和亲和素的特异性反应进行检测,结果传感器的灵敏度为0.9 pg/Hz,分辨可达到49 fg.本文还着重介绍了为谐振梁传感器设计的以锁相环(Phase-Locked Loop简称PLL)为核心的闭环接口电路,分析了悬臂梁和电路在闭环系统中的工作特性,并探讨了解决谐振式传感器在使用中常见的稳定性差、噪声干扰强等问题的方法. 相似文献
7.
8.
针对微小集中质量测量问题,提出并制备了一种梯形变截面悬臂梁式微质量传感器,建立了梯形变截面悬臂梁式微质量传感器的振动分析模型。采用有限元方法求解其振动控制方程,获得了微质量传感器的灵敏度。仿真分析结果表明,相对于等截面矩形悬臂梁式微质量传感器,单层压电和双层压电结构的变截面悬臂梁传感器的灵敏度分别提高了127.00%和263.00%。采用线切割工艺,加工制备了单压电层梯形变截面结构的微质量传感器并对传感器进行了实验测试,在误差允许范围内,仿真结果与实验结果基本一致,验证了采用梯形变截面悬臂梁式结构可以有效的提高传感器的灵敏度。 相似文献
9.
10.
11.
对比传统的CCD信号处理电路,提出了CCD信号处理集成化方案。简述了传统的CCD信号处理电路工作原理,介绍了其基本功能。根据CCD器件的工作原理,对CCD器件输出信号的特性进行了详细分析。针对CCD信号存在的复位噪声,对相关双采样电路的基本原理进行了详细介绍。传统的CCD信号处理电路一般由前置放大电路、相关双采样电路、可编程增益放大电路和AD转换电路等分立电路组成,结构复杂、调试困难、功耗紧张等缺点是显而易见的;而集成化处理方案则采用FPGA结合ADC的处理模式,集成度高、结构简单、灵活性强是不言而喻的。最后,通过一设计实例对方案进行设计验证,并对设计中应注意的一些问题进行了详细分析和总结。 相似文献
12.
In this paper, a new concept and potential demonstration of functional microfluidic integrated circuits using MEMS technology are presented. The fluidic integrated circuits were constructed utilizing analogous relationship between MOSFET and pneumatic microvalve with a diaphragm structure. The signal transmitted through the circuit is the fluidic signal, that is, the pressure or the flow-rate of the fluid. The pneumatic microvalve in this study is expressed by small-signal equivalent model similar to that of a MOSFET. Small signal behavior of microfluidic integrated circuits can be expected using the model, if the parameters in the model are extracted properly from fabricated microvalves. As an example of a fluidic circuit, pressure inverting amplifiers including integrated two microvalves were fabricated and evaluated. As a result, they showed sharp pressure transfer curves similar to MOS inverter circuits. A maximum pressure gain of 32.0 dB was obtained, and it can be used for pressure amplification in analog applications. In addition, they can be used as pressure inverter logic circuits for digital applications. Although the theory and design environment of the new microvalve circuit technology have not been established yet, multifunctional fluidic analog and digital circuits can be realized for special application fields different from electronic integrated circuits. 相似文献
13.
This paper proposes the use of the current signal to express logic values and establishes th theory of grounded current switches suitable for I^2L circuits.Based on the advantag that current signals are easy to be added,the design technique of I^2L circuits by means of the multi-valued current signal is proposed.It is shown that simpler structure of I^2L circuits can be obtained with this technique. 相似文献
14.
I. I. Lee 《Optical Memory & Neural Networks》2009,18(1):44-54
Structure and circuit solutions for implementing adaptive multichannel analog and digital signal preprocessing circuits integrated
with readout circuits are considered. Experimental results of investigating multichannel signal preprocessing readout circuits
and IR FPA based on them are represented.
The article is published in the original. 相似文献
15.
16.
17.
Marius Bozga Hou Jianmin Oded Maler Sergio Yovine 《Electronic Notes in Theoretical Computer Science》2002,65(6)
In this work we apply the timing verification tool OpenKronos, which is based on timed automata, to verify correctness of numerous asynchronous circuits. The desired behavior of these circuits is specified in terms of signal transition graphs (STG) and we check whether the synthesized circuits behave correctly under the assumption that the inputs satisfy the STG conventions and that the gate delays are bounded between two given numbers. Our results demonstrate the viability of the timed automaton approach for timing analysis of certain classes of circuits. 相似文献
18.
介绍了系统信号调理电路和以DSP及模数转换器ADS7805为核心的信号采样电路,结合快速傅里叶变换介绍了系统参数测量的主程序及服务子程序,最后对系统应用中的测量精度进行了分析。实验表明该仪器测量电压精度达0.5级,频率分辨率达20Hz。 相似文献
19.
文中提出了一种采用计数器存储权值的人工神经网络的实现方案。数字权值采用计数器存储,突触电路和神经元电路用模拟电路来实现。数字权值经脉冲宽度调制电路转换为脉冲信号作为模拟突触电路的输入信号。因而权值可以长期存储,对权值的修改易于实现,突触神经元电路结构简单,融合了人工神经网络模拟实现和数字实现的优点。对于智能计算机的实现具有重要的意义。 相似文献